Atoms, Molecules, & Ions
Identify the protons, neutrons, and electrons for Ag+2.
What is....
Protons: 47
Neutrons: 61
Electrons: 49
Determine the number of moles in 250.0g of CaCO3.
What is...
2.50 mols
Balance the equation:
Cu(π )+HNO3(ππ)βΆCu(NO3)2(ππ)+H2O(π)+NO(π)
What is...
3Cu(π ) + 8HNO3(ππ) βΆ 3Cu(NO3)2(ππ) + 4H2O(π) + 2NO(π)
How much heat, in joules, is required to heat a 28.4-g (1-oz) ice cube from β23.0 Β°C to β1.0 Β°C?
What is...
1310 J
An element has the following natural abundances and isotopic masses: 90.92% abundance with 19.99 amu, 0.26% abundance with 20.99 amu, and 8.82% abundance with 21.99 amu. Calculate the average atomic mass of this element.
What is...
20.18 amu
What is the difference between molecular formulas and empirical formulas?
Molecular formulas account for every atom in the molecule.
Empirical formulas show the simplified ratio of atoms in a molecule.
Determine the mass of 2.345 mols of LiCl.
What is...
99.41g
List 3 strong acids and 3 strong bases.
What is...
Acids: HCl, H2SO4, HBr, HI, HClO4, HNO3
Bases: NaOH, KOH, LiOH, RbOH, CsOH, Ba(OH)2, Sr(OH)2, Ca(OH)2
How much heat, in joules, must be added to a 75.0βg iron block with a specific heat of 0.449 J/g Β°C to increase its temperature from 25 Β°C to its melting temperature of 1535 Β°C?
What is...
5.09Γ104 J
Determine the molarity of 0.005653 mol of Br2 in 10.00 mL of solution.
What is...
0.5653 M
Erwin Schrondinger discovered this theory that identifies the location probability of electrons.
What is...
Quantum Mechanical Model
A 55-kg woman has 7.5 Γ 10β3 mol of hemoglobin (molar mass = 64,456 g/mol) in her blood. How many hemoglobin molecules is this? What is this quantity in grams?
What is...
4.52Γ1021 molecules hemoglobin
483.4 g hemoglobin
Identify the atoms that are oxidized and reduced, the change in oxidation state for each, and the oxidizing and reducing agents in each of the following equations:
Mg(π ) + NiCl2(ππ) βΆ MgCl2(ππ) + Ni(π )
What is...
Mg - oxidized
Ni - reduced
Reducing agent: Mg
Oxidizing agent: Ni
When 2.50 g of methane burns in oxygen, 125 kJ of heat is produced. What is the enthalpy of combustion per mole of methane under these conditions?
What is...
β802 kJ molβ1
Calculate the enthalpy of combustion of butane, C4H10(g) for the formation of H2O(g) and CO2(g). The enthalpy of formation of butane is β126 kJ/mol.
Standard states:
C4H10 (-126kJ/mol); CO2 (-393.5kJ/mol); H2O (-241.8kJ/mol); O2 (0kJ/mol)
What is...
β2660 kJ molβ1
What is...
52.0 amu
If 0.1718 L of a 0.3556-M C3H7OH solution is diluted to a concentration of 0.1222 M, what is the volume of the resulting solution?
What is...
0.5000 L
What is the limiting reactant when 1.50 g of lithium and 1.50 g of nitrogen combine to form lithium nitride, according to the following unbalanced equation?
Li + N2 βΆ Li3N
What is...
Lithium
A 50.0 mL sample of 0.600 M HCl is mixed with 30.0 mL of 1.00 M NaOH in a coffee-cup calorimeter. The temperature rises from 24.5 Β°C to 29.8 Β°C.
Assume density = 1.00 g/mL, c=4.184 J/gΒ°C
(a) Determine the limiting reactant and how many moles of water are formed.
(b) Calculate the enthalpy change ΞH\Delta HΞH for the reaction per mole of water formed.
What is...
(a) They are equalβ both are completely consumed.
Moles HβO formed (1:1 HβΊ:OHβ») = 0.0300 mol.
(b) β5.91Γ104 J/mol
Identify the atoms that are oxidized and reduced, the change in oxidation state for each, and the oxidizing and reducing agents in each of the following equations:
Zn(π ) + H2SO4(ππ) βΆ ZnSO4(ππ) + H2(π)
What is...
Zn - oxidized
H - reduced
Reducing agent: Zn
Oxidizing agent: H
Name these compounds and identify if they are ionic or covalent.
CCl4
H3P
Fe(NO3)
NH4Cl
What is...
Carbon Tetrachloride - Covalent
Trihydrogen phosphide - Covalent
Iron (III) nitrate - Ionic
Ammonium Chloride - Ionic
Dichloroethane, a compound that is often used for dry cleaning, contains carbon, hydrogen, and chlorine. It has a molar mass of 99 g/mol. Analysis of a sample shows that it contains 24.3% carbon and 4.1% hydrogen. What is its molecular formula?
What is...
CβHβClβ
2C8H8O2 + Cu2O βΆ 2CuC8H7O2 + H2O
How many grams of copper(I) oxide (Cu2O) are needed to produce 15.0 g of CuC8H7O2?
(Use MM CuC8H7O2 = 217.20 g/mol).
What is...
4.94 g of CuβO
Explain the difference between heat capacity and specific heat of a substance.
What is...
Heat capacity refers to the heat required to raise the temperature of the mass of the substance 1 degree; specific heat refers to the heat required to raise the temperature of 1 gram of the substance 1 degree. Thus, heat capacity is an extensive property, and specific heat is an intensive one.
What volume of a 0.3300-M solution of sodium hydroxide would be required to titrate 15.00 mL of 0.1500 M oxalic acid?
C2O4H2(ππ) + 2NaOH(ππ) βΆ Na2C2O4(ππ) + 2H2O(π)
What is...
13.64 mL